Installation of the Service Pack 1 update package for Windows 7 and Windows Server 2008 R2 fails with "Service pack installation can't continue"

Applies to: Windows Server 2008 R2 Service Pack 1Windows 7 Service Pack 1


While installing the Service Pack 1 update package for Windows 7 or Windows Server 2008 R2, an error window may appear as shown below:

Window title:  Install Windows Service Pack

Message Text:

Service Pack installation can't continue

Software installed on this computer isn't compatible with the service pack. Click the link for more information about this problem.

After the problem is resolved, restart the installation.

Microsoft Security Essentials - your version of this program may prevent successful installation of this service pack.

Go online for details ("Go online for details" is a link that points to: Why am I receiving a message about Microsoft Security Essentials or Microsoft Forefront Client Security when installing a service pack?


While preparing your computer for installation of the service pack, a check is performed to ensure that a filter driver,mpfilter.sys, commonly installed with Microsoft Security Essentials, Microsoft Forefront Client Security, and Microsoft Forefront Endpoint Protection is at a file version level greater than or equal to 2.1.6804.0. This is to prevent a known deadlock situation, which can lead to a hang during the service pack installation. 


The resolution depends on the anti-malware product and version you are running. To determine the product and version click Start, type "uninstall a program", then select the "Uninstall a program" Control Panel item in results. (Or click Start, Control Panel, Programs, Uninstall a program). Note the name and version of the security product installed.

Microsoft Security Essentials

If you do not have version 1.0.1963.0 or later installed, upgrade using the instructions in KB2254596, or launch Microsoft Update and install the update or a newer version from there.

Forefront Client Security

For already installed FCS client installations, install the update for Microsoft Knowledge Base article 2394433.
For new FCS Client installations, deploy the client components listed in Microsoft Knowledge Base article 2394439.

 Microsoft Forefront Endpoint Protection

Upgrade to the latest version of the product. The product version is not necessarily upgraded during anti-malware definition updates. Additionally, if a beta version of FEP is currently installed, the product version displayed in Help, About might appear to be a higher version number than the RTM version of the product. The determine whether you have a version that is compatible with Windows 7 SP1, check the file version for mpfilter.sys in the locations specified under More Informaiton.

It might be necessary to uninstall the current version before installing a new one.

Warning: Uninstalling Microsoft Forefront Endpoint Protection might make your computer (and your network, if you have one) more vulnerable to viruses, worms, or hackers. Reinstall Microsoft Forefront Endpoint Protection promptly to minimize the time your computer is unprotected.

Once the anti-malware product has been upgraded, attempt the service pack installation again.

More Information

 Mpfilter.sys is typically installed into one of the following folders:
  • %ProgramFiles%\Microsoft Forefront\Forefront System\Client\AntiMalware\Drivers\mpfilter
  • %ProgramFiles%\Microsoft Security Client\Antimalware\Drivers\mpfilter